Weighing scale



Dec. 4, 1934. w. D. WATLlNG WEIGHING SCALE Filed June 21, 1934 2 Sheets-Sheet l 1934- w D. WATLING WEIGHING SCALE Filed June 21, 1934 2 Sheets-Sheet 2 Patented Dec. 4, 1934 UNITED STATES WEIGHIN G SCALE William D. Watling,

Chicago, Ill., assignor to Watling Manufacturing Company, Chicago, 11].,

a corporation of Illinois Application June 21, 1934, Serial No. 731,701 5 Claims. 19447) This invention relates to c weighing scales and is particula use in connection with that type of scales wherein the weight indicator is normally locked by a latch which is adapted to be retracted to release the indicator by means of a coin actuated tripper. In such devices the tripper, when operated by a coin of proper denomination, lifts the latch into position to be supported by a dog which is intended to hold the latch in retracted position until the completion of the weighing operation. The dog is automatically tripped for the purpose of releasing the latch to again lock the weight indicator at the end of the weighing operation. In scale mechanisms of this type heretofore in use, it was possible, by the use of a light weight slug, to disable the latch so as to obtain an indefinite number of free weight indicating operations. This was due to the fact that a light weight slug, of less weight than the intended coin, would not slide from the tripper into the usual coin receptacle, but would remain on the tripper so as to shift the tripper to an intermediate position sufficient to retract the latch from its locking position but insuflicient to raise the latch onto the dog which was intended to support the latch during one weight indicating operation. As a result, the latch was supported in an intermediate retracted position by the tripper instead of being supported in its fully retracted position by the dog and, inasmuch as the tripper was retained indefinitely in its intermediate position by the light weight slug, it was possible to secure an indefinite number of free weight indications.

The main objects of this invention are to provide a weighing scale having improved means for insuring the release of the latch so as to lock the indicator after each weight indicating operation.

An illustrative embodiment of this invention is shown in the accompanying drawings wherein:

Figure 1 is a fragmentary rear elevation of the head of an improved scale, certain parts being omitted for the sake of cleamess.

Figure 2 is a vertical section taken on the line 22 of Figure 1.

Figure 3 is a fragmentary rear elevation showing the latch lifted to inoperative position by the tripper, which is shown in full outline at the limit of its operative stroke and which is shown in dotted outline in an intermediate position which would be sufiicient to retract the latch from its locking position but insufiicient to raise the latch onto the supporting dog.

Figure 4 is a perspective of the arm which is oin controlled rly adapted for adapted to complete the stroke of the tripper from the position shown in dotted outline in Figure 3 to the position shown in full outline.

Figure 5 is a fragmentary rear elevation showing the latch and its supporting dog, the latch being shown in full outline in looking position and in dotted outline supported on top of the dog.

In the construction herein shown, the scale comprises an upright casing 1 in which is housed an indicator drum 2 adapted to be rotated by a vertically movable rack bar 3 which is controlled by weight actuated mechanism 4. The indicator is normally locked by a latch 5 adapted to be tripped by a coin-actuated tripper 6.

The casing 1 comprises a column 7 having a head 8 provided with a rear plate 9 which is removable to permit access to the mechanism. The upper end of the head has a window 10 through which the indicator is visible.

Mounted on the head, is a coin chute 11 having an inlet slot 12 at its upper end and having its lower end arranged to discharge coins onto the tripper 6. Mounted within the casing, is a supporting frame comprising a front plate 13 and a rear plate 14 connected to bolts 15 having sleeves 16 for spacing the plates apart. This frame is supported on bolts 17 secured to the front wall of the casing and provided with spacing sleeves 18.

The indicator drum 2 is fixed on the forward end of a shaft 19 which is journaled in the frame plates 13 and 14. The weight indicating numbers are printed on or otherwise applied to the rim of this drum. Supported directly above the drum, is a shield 20 having a centrally located opening 21 through which the weight indication is visible. This shield may bear advertising or other printed matter. The shield is secured to the front plate 13 by a bracket 22.

Fixed on the indicator shaft 19, is a pinion 23 which is in constant mesh with the rack bar 3.

The rack bar 3 is vertically shiftable in a guide member 24 which is secured to the front plate 13 by screws 25. On the upper end of the rack bar, is a laterally projecting pin 26 which carries a weight 27 which is arranged to urge the rack bar toward the pinion 23 and which also takes up any slack which might exist between the intermeshing teeth of the rack and pinion. The rack bar 3 is normally secured against vertical movement by the pinion 23 which is prevented from rotating by the latch 5. However, upon release of the indicator shaft, the rack bar is permitted to move downwardly by gravity for rotating the indicator shaft to actuate the indicatordrum. The extent of the downward movement of the rack bar is determined by the weight actuated mechanism.

The weight actuated mechanism comprises a yoke 28 secured to the upper end of a rod 29 which is connected at its lower end to the usual weighing platform, not shown, for lowering the rod and yoke.

The yoke is counterbalanced by a pair of weighted pendulums 30 having trunnions-31'provided with the usual knife edge pivots engaging suitable seats on the frame. are fixed on the trunnions 31 and twofiexible metal bands 33 are attached to and extend over the faces of the cams. The lower ends of these "the completion of a weighing operation, as the segment 60 moves clockwise, the teeth of the segbands are connected respectively to the ends of a cross bar 34 pivotally mounted on a pivot pin 35 supported in a bifurcated portion upper end of the yoke. The cams are so shaped that the extent of movement of these partsis directly proportional to the weight upon the scale pl fo Supported on the upper end of the yoke, is a lever 37 which is pivotally secured to the yoke by a pin 38. The forward end of this lever is bent upwardly to form a stop 39 for engaging the lower extremity of the rack bar to limit the downward movement of the rack bar. The rear end of the lever 37 has a counterweight 4O resting upon a set screw 41 which is mounted on a bracket 42 secured to the yoke. By means of the set screw 41, the rack bar may be vertically adjusted so as to accurately set the indicator drum at the zero position when there is no weight on the platform.

Movement of the yoke may be cushioned by the usual dash pot 43 having a piston 44 provided with ,a rod 45 which is connected to the upper portion of the yoke. The dash pot is supported on a bracket 46 secured to the rear wall of the casing.

In the form shown, the latch 5 comprises a lever'having one end pivotally secured to a supporting pin 47. The free end of the lever has a projection 48 which is adapted to coact with a toothed wheel 49 fixed on the shaft 19 for locking the indicator drum against rotation. The latch is arranged so as to normally drop by gravity into its locking position. Formed on the latch 5, is a bent arm 50 which the tripper 6 engages for retracting the latch upon the insertion of a coin.

Carried by the latch, is a collar 51 having a lug 52 which is adapted to rest on top of a dog 53 for supporting the latch in its fully retracted position during each weighing operation. The collar has a set screw 54 which permits adjustment to accurately position the lug 52 relative to the d The dog 53 is pivoted on a pin 55 supported on a bracket 56. Stops 57 and 58 on the bracket 56 limit the pivotal movement of the dog. The pivot of the dog is positioned so that the dog normally assumes the upright position shown in Fig. 5. On one side of the dog, is a cam edge 59 which engages the lug 52 so that, when the latch is moved upwardly under the action of the tripper, the dog is rocked on its pivot until the-lug 52 is above the dog, whereupon the dog drops back intothe position shown in Fig. 5 for supporting the latchin retracted position during a weighing operation.

, At the completion of a weighing operation, the dog 53 is retracted from the lug 52, in order to permit the latch to again drop into engagement with the wheel 49, by means of a toothed segment 60 pivotally mounted on a pin 61. This segment "movement of the pawl is limited by a pair of stops 6'7. A pair of cams""32 36 on the in dotted outline in Fig.

has an arm 62 connected to a link 63 which is connected to an arm 64 on the yoke 28 so that, when the yoke moves downwardly the segement is shifted counter-clockwise as Viewed in Fig. 5, and when the yoke moves upwardly the segment moves clockwise. The position of the segment shown in Fig. 5 is the normal position.

Carried by the dog 53, is a pawl 65 pivotally secured to the dog by a pin 66. The pivotal When the segment 60 moves counter-clockwise during the weighing operation, the pawl 65 merely rides on the teeth of the segment so as to oscillatebetween the stops 67. However, upon whereupon the latch drops into locking engage- 'ment with the wheel 49.

The coin actuated tripper 6 is in the form of a lever having a pivot pin 68 supported in-a bearing member 69 which is mounted on the rear frame plate 14. One end of the tripper has a;; cup 70 and the opposite end has a weight '71 which normally positions the lever as shown in Fig. l with the cup 70 located directly below the coin chute for receiving a coin from the chute. The tripper lever has an arm 72 which projects forwardly for engaging the latch arm 50 to lift the latch when the tripper is rocked under the weight of a coin in the cup '70. 'If the coin is of the proper denomination, the tripper is rocked sufficiently to lift the latch on top-m0 of the dog 53. However, if a light coin or paper slug is used in an endeavor to cheat the machine, the tripper might stop in the position shown 3, which would be sufficient to release the weight indicator but insuffi 5 cient to place the latch on top of the dog 53. The coin is intended to slide through the open end of the cup 70 when the tripper is shifted tothe limit of its stroke but if the tripper is held in the dotted line position of Fig. 3, the coin remains in the 31% cup and permits an indefinite number of weighing operations. To prevent this, means is provided for completing the operative movement of the tripper.

As shown in Figs. 1 and 3, the tripperhas a3125 finger 73 located in the normal path of a dog 74 pivotally secured to a rocker arm '15 by a pin '76. The rocker arm 75 is fixed on the'indicator shaft 19 so as to move with the indicator drum. Movement of the dog 74 relative to the arm 76 is limited by shoulders 77 and 78 on the rocker arm. When the indicator drum is restored to zero position, the rocker arm 75 moves counterclockwise, as viewed in Figs. 1 and 3, and this causes the dog '74 to drop against theshoulder 77 as shown in Fig. 1. If, therefore, the indicator is again released and the tripper is retained in an intermediate position, when the rocker arm '75 swings upwardly the dog '74 will strike the finger '73 and rock thetripper sufficiently to lift the latch 5 on the top'of the dog 53."'

Also formed on the tripper 6, is a short finger '79 which is adapted to engage the dog 74'f'or shifting the dog against the shoulder 78 when'the tripper is operated by acoin of proper denQmination. After the'dog '74 is shifted intoengage ment with the shoulder 78 as shown inFig. 3, it will clear the finger-73. 1

In operation, I a weight-uponthe platform P-of the scales moves the yoke 28 downwardly whichaif swings the pendulums 30 outwardly, but the rack bar 3 remains locked by the pinion 23. When a coin of proper size is deposited, it swings the tripper 6 to the full line position of Fig. 3, thereby lifting the latch 5 onto the dog 53 so as to release the indicator drum. When the scale platform begins to move upwardly, the segment 60 rocks the dog away from the lug 52 and the latch drops into locking engagement with the wheel 49.

If the tripper 6 is moved only to an intermediate position by a light weight slug, the dog 74 engages the finger 73 to complete the stroke of the tripper, thereby preventing more than one weight indicating operation for each coin which is deposited.

Although but one specific embodiment of this invention has been herein shown and described, it will be understood that details of' the construction shown may be altered without departing from the spirit of the invention as defined by the following claims.

I claim:

1. A scale comprising a weight-actuated mechanism, a weight indicator controlled by said mechanism, a latch normally locking said indicator in zero position, a dog for retaining said latch in a retracted position during a weighing operation, means actuated by said mechanism for tripping said dog when the load on said mechanism is reduced, a coin actuated tripper movable a, predetermined distance by the Weight of a coin predetermined distance.

2. A scale comprising a weight-actuated mechanism, a weight indicator controlled by said mechanism, a latch normally locking said indicator in zero position, a dog for retaining said latch in a retracted position during a, weighing operation,

predetermined weight for positioning said latch in engagement with said dog, and auxiliary means connected to said indicator for moving said tripper the remainder of said predetermined distance when said tripper has stopped short of its full stroke after releasing said indicator.

3. A scale comprising a counterbalanced weightactuated member adapted to be shifted to difierent positions in accordance with the load thereon, a shiftable indicator adapted to be arrested by said member in different indicating positions, a rotatable shaft for said indicator, a latch normally locking said indicator in zero position, a dog adapted to retain said latch in a retracted position during a weighing operation, means for tripping said dog to permit said latch to relock said indicator when the load on said member is reduced, a coin-actuated tripper movable a predetermined distance by the weight of a coin of weight for positioning said latch in operative engagement with said dog, and a rotatable element mounted on said indicator shaft and adapted to move said tripper the remainder of said predetermined distance when said tripper has stopped short of its full stroke after releasing said indicator.

4. A scale comprising a counterbalanced weightactuated member adapted to be shifted to different positions in accordance with the load thereon, a shiftable indicator adapted to be arrested by said member in different indicating positions, a rotatable shaft for said indicator, a latch normally locking said indicator in zero position, a dog cator shaft, and a pawl carried by said arm and movable into engagement with said tripper for moving said tripper the remainder of said predistance when said tripper has stopped short of its full stroke after releasing said indicator.

5. A scale comprising a counterbalanced weight-actuated member adapted to be shifted to difierent positions in accordance with the load thereon, a shiftable indicator adapted to be arrested by said member in different indicating positions, a rotatable shaft for said indicator, a latch normally locking said indicator in zero position, a dog adapted to retain said latch in a retracted position during a weighing operation, means for tripping said dog to permit said latch to relock said indicator when the load on said member is reduced, a coin-actuated tripper movable a predetermined distance by the weight of a coin of predetermined weight for positioning said latch in operative engagement with said dog, a pawl carried by said indicator shaft and movable thereby into engagement with said tripper for shifting said tripper the remainder of its operative stroke when said tripper has stopped short through the use of a coin of insuflicient weight, and means on said tripper for disabling said pawl when said tripper has been actuated by a coin of less than said predetermined weight.

WILLIAM D. WATLING. 

